1. Field
The present disclosure relates to a fuel cell system and to a method of shutting down the fuel cell system.
2. Description of the Related Art
When a fuel cell system of this type is shut down, supply of fuel gas and oxidant gas to a fuel cell is stopped. At this point, the oxidant gas remains in the cathode side of the fuel cell (an oxidant gas flow path for introducing the oxidant gas to the cathode electrode of the fuel cell). When the oxygen in the oxidant gas is left remaining in the cathode electrode of the fuel cell, the catalyst included in the fuel cell may deteriorate and the durability of the fuel cell may be reduced.
For instance, Japanese Unexamined Patent Application Publication No. 2013-149538 discloses a technical idea in which when a fuel cell system is shut down, power generation of the fuel cell is continued in a state where supply of oxidant gas to the cathode side of the fuel cell is stopped, and the oxygen consumption processing is thereby performed to cause the oxygen in the oxidant gas on the cathode side of the fuel cell to be consumed. In addition, the fuel cell system determines based on the output voltage of the fuel cell whether or not the oxygen on the cathode side of the fuel cell has been sufficiently consumed.